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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 2 |
| 6 | 3 |
| 7 | 26 |
| 8 | 53 |
| 9 | 111 |
| 10 | 77 |
| 11 | 480 |
| 12 | 5 |
| 13 | 2080 |
| 14 | 333 |
| 15 | 1001 |
| 16 | 18747 |
| 17 | 39014 |
| 18 | 20297 |
| 19 | 168954 |
| 20 | 117199 |
| 21 | 731679 |
| 22 | 1522639 |
| 23 | 3168640 |
| 24 | 16485 |
| 25 | 653440 |
| 26 | 28556241 |
| 27 | 59426081 |
| 28 | 9512831 |
| 29 | 257352966 |
| 30 | 14876567 |
| 31 | 1114503066 |
| 32 | 2319302053 |
| 33 | 4826511631 |
| 34 | 10044062391 |
[0,1,1,3,2,3,26,53,111,77,480,5,2080,333,1001, 18747,39014,20297,168954,117199,731679,1522639, 3168640,16485,653440,28556241,59426081,9512831, 257352966,14876567,1114503066,2319302053, 4826511631,10044062391] |